Gear-hobbing machine.



W. NATISCH.

GEAR HOBBING MACHINE.

APPLICATION FILED MAY 22. 1916.

1,213,236. Patented Jan. 23,1917.

3 SHEETSSHEET l- IN V EN TOR.

I Y a His ATTORNEY umulm 1mm W I W. NATISCH.

GEAR HOBBING MACHINE.

APPLICATION FILED MAY 22, 1916.

Patented Jan. 23, 1917.

- a SHEETSQ-SHEET 2.

wam/@2404 INVENTOR.

H55 ATTORNEY W. NATISCH.

GEAR HOBBING MACHINE.

APPLICATION FILED MAY 22. 1916. I 1,213,236. 7 Patented Jan. 23, 1917.

3 SHETS-SHEET 3. 7/.

IN V EN TOR.

r HIS ATTORNEY i WM r WILLIAM NATISCH, 0F GBEATKILLS, NEW YORK.

GEAR-HOBBING MACHINE.

Application filed May 22, 1916. Serial No. 99,048.

To all whom it may concern Be it known that I, l/VILLIAM NA'rIson, a citizen of the United States, and residing at Greatkills, Staten Island, in the county of Richmond and State of New York, have invented certain new and useful Improvements in Gear-Hobbing Machines, of'which the following is a specification.

This invention relates to metal working machines and particularly to the type of machines known as gear hobhing machines adapted to mill spiral gears'by means of a cutter or hob.

The object of this invention is the elimination of vibrations of the cutter or hob during the operation of cutting and as a result thereof, the production of smoother surfaces of the gear teeth, out with my improved machine.

lVith these and other objects in view. the invention consists in certain novel details of construction and arrangements of parts hereinafter described and particularly set forth in the appended claims.

leference is to be had to thw accompanying drawings, forming part of this specification in which- Figure I is a side elevation of the main part of a gear hobbing machine, equipped with my invention. Fig. II is a frontelevation of Fig. I. Fig. III is a sectional elevation of the hobbing mechanism on the line A-A of Fig. VI. Fig. IV is a plan view of the bobbing mechanism. Fig. V is a vertical section on line 'B-B of Fig. VI. Fig. VI is a front elevation of the hobbing mechanism of my gear bobbing machine.

Similar letters of reference indicate corresponding parts throughout the various figures.

Referring to the drawii'igs, 1 is the horizontal bed of the machine on which the housing is slidably mounted and adapted to be fed by a suitable feeding mechanism toward and away from the vertical column 3 of the machine. Table 2 is rotatably mounted on tablehousingi! and arbor 4. which holds the work or gear blank is mounted on table 9. which is subject to a rotary feeding motion by a suitable feeding mechanism.

Specification of Letters Patent.

Patented Jan. 23, 1917.

Column 3 is preferably of hollow, rectangular cross-section, and provided with vertical bed guides 6, on which the bobbing mechanism, shown in Figs. III, IV, V and VI, slides, cutter slide 7 engaging the bed guides 6 of column 3, the front side of the column 3 on which the hobbing mechanism slides being preferably left open. Cutter slide 7 is provided with a circular T slot 8 in which the T bolts 9 slide. Cutter head 10 is rotatably mounted on cutter slide 7 by means of shoulder 10 and flange 10", while bolts 9 serve to clamp the cutter head, at any desired angle, to cutter slide 7. Bearings 11 are mounted on cutter head 10 on each side of its center of rotation, these hearings hold the hobarbor 12 and are slidahly fastened to the cutter head by means of T bolts 13 running in slots 13 of the cutter head and T bolts 9 clamp these bearings directly to cutter slide 7. Hob 14 receives its rotary motion through arbor 12 from spur gear 15 mounted thereon, within opening 16 of the cutter head. Gear 15 is driven. by a spur pinion 17 located above, this gear on a horizontal spindle 18 journaled in the out ter head and parallel to arbor 12. The opposite end of spindle 18, near the axis of the cutter head is provided with a bevel gear 19, which meshes into a similar bevel gear 20, attached to the front end of shaft 21 which is directed toward the interior of column 3, and journaled in a bearing 22 fastened to or forming a part of cutter head 10, and located vertically above the center of rotation of the cutter head. The rear end of shaft 21 is provided with a spur gear 23, which is driven by a similar spur gear 24, mounted on the front end of the intermediate horizontal spindle the axis of this shaft is coincident-with the axis of rotation of cutter head 10, and thespindle 25 is journaled in bearing 26, which is'fastened by arms 7 to cutter slide 7 and capable of vertical movement with the latter. The rear end of spindle 25 carries bevel gear 27 which receives motion from bevel pinionQS mounted on a hollow vertical spindle '29. Thisspindle travels on the vertical.- shaft 30 from which it receives rotary motion by means of the keys 31, and keyways 81. Journal 32 in which the hollow spindle 29 revolves, is fastened to arms 7. Shaft 30 receives its rotary motion in any suitable manner from the driving mechanism of the machine.

In gear hobbing machines of the kind described, it is of greatest importance to avoid vibrations of the hob when cutting, as such vibrations of the hob produce chattering and uneven surfaces of the gear teeth produced by the machine. The present invention is principally intended to rectify these defects by an improved fastening of the hob arbor to the column of the machine and by the reduction of the distance between the axis of the hob and the column (marked D in Figs. I and III). I accomplish this reduc tion of the distance Dlby the introduction of the planetary spur gears 23 and 24, which in my machine are located inside of column 3, and by this means, I am enabled to place shaft 18 outside of column 3 in a position not affecting the distance between gear 15 and column 3, which is the case where gear 19 meshes directly into a bevel gear mounted on shaft 25, which brings shaft 18 between gear 15 and column 3.-

By elimination of a shaft between the arbor 12 and column 3, I am enabled to provide the cutter head 10 with the recess 10 in which'the body parts of the journals 11 slide in close proximity to column 3, furthermore, I have fastened these journals directly to the circular T slot of the cutter slide 7 by bolts 9 whereby all vibration of intermediate parts is eliminated.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a machine of the kind described, a

. cutter slide, a cutter head rotatably mounted therein, a hob arbor attached to said cutter head, the aXis of said hob arbor lying in the same plane with the axis of rotation of said cutter head and a driving spindle for said hob arbor, whose axis is located outside of the plane through the axes of cutter head and hob arbor.

2. In a machine of the kind described, a cutter slide, a cutter head rotatably mounted therein, said cutter slide being adapted to slide perpendicularly to the direction of the cutter head axis, a hob arbor and a spindle driving said arbor, carried by said cutter head, a shaft supplying power to said spindle and a bearing for said shaft attached to the cutter head.

3. In a machine of the kind described, a cutter slide, a cutter head rotatably mounted therei z 1 said cutter slide being adapted to "slideperpendicularlyto the direction of the cutter head axis, a hob arbor, a driving spindle in geared connection with said hob arbor and an intermediate shaft geared to said driving spindle carried by said cutter arness head the axis of said intermediate shaft be ing parallel, but eccentric to the axis of, rotation of the cutter head.

. d. In a machine of the kind described, a

.cutter slide, a cutter head, rotatably mountnaled in said cutter slide coaxially with the aXis of rotation of said cutter head and geared to said power shaft and a pair of planetary gears within said column totransmit power from the horizontal shaft to the cutter head.

6. In a machine of'the kind described,'a.

supporting column, a cutter slide movabl attached thereto, an intenmediate shaft and a cutter head rotatahly and coaxially carried by said cutter slide, a second intermediate shaft eccentrically journaled in said cutter head and a pair of spur gears to transmit power from the first to the second interme diate shaft.

7. In a machine of the kind described, a-

cutter slide, a cutter head rotatably mounted therein, a pair of bearings removably attached to said cutter head, a hob, a hob carrying arbor journaled in said bearings, --a spindle, driving said arbor carried by said cutter head and located outside of a plane through the cutter head and hob arbor axes, said hob, hob arbor and bearings being partly inclosed by said cutter head.

8. In a machine of the kind described, a

cutter slide, a cutter head rotatably mounted therein, bearings attached to said cutter hcad,'a hob and a hob carrying arbor journeled in said bearings, and clamping means, slidably connected to said cutter slide and fixed to said cutter head to clamp said bearings and said cutter head to said cutter slide.

9. In a machineof the kind described, a supporting column, a cutter slide movably attached thereon, a power supply shaft within said column, an intermediate shaft carried by said cutter slide geared thereto, a cutter head in coaxial relation to said intermediate shaft, rotatably mounted in said cutter slide, a second intermediate shaft carried by said cutter head in eccentric position thereto, geared to the first intermediate shaft, a hob arbor, and bearings therefor connected to said cutter head, a driving spindle for said hob arbor geared thereto and to the second intermediate shaft, and

by said cutter slide, a hob arbor, and a driving shaft geared thereto, transverse to the axis of said cutterrhead, the axis of the driving shaft being located outside of a plane through the cutter head and hobarbor J 0 axes and means to supply power to said driving shaft comprising a pair of intc1u'1e diate shafts one of said shafts being r0tatably connected to the cutter head and the other to the cutter slide.

WILLIAM NATISCH. 

